11:19 p.m.|Wrap Up

That’s it for tonight. One incumbent, Senator Arlen Specter, lost in a tough primary against Representative Joe Sestak, who surged in the last few weeks. The outcome in Pennsylvania ended the five-term Senate career of Mr. Specter, who switched parties last year to avoid what he believed was a certain defeat as a Republican.

Senator Blanche Lincoln of Arkansas faced an uphill battle against the popular lieutenant governor, Bill Halter. Neither reached the 50-percentage threshold, so they’ll got to a runoff on June 8.

From Shaila Dewan: At her brightly lit election night party at the Holiday Inn Presidential, Ms. Lincoln addressed the crowd and proposed a couple of ground rules for the three-week runoff.

“I want to call on Bill Halter to end all of his negative ads, and I will too,” she said. “We also need to call on every one of these outside groups to take their negative ads down and go home. We need to make this campaign about Arkansas and the people of Arkansas and who we are and what we believe in.”

Labor unions and other independent groups have spent millions of dollars on the races in Arkansas.

And in Kentucky, the Republican primary went to Rand Paul, the Tea Party candidate, a victory that will certainly be mined for street party credentials across the country as Republicans face intraparty strife.

10:58 p.m.|Run-Off in Arkansas

Neither Democratic candidate, Senator Blanche Lincoln or Lt. Gov. Bill Halter, reached the 50 percent threshold in the Democratic primary in Arkansas. That means they’ll face each other again in a run-off election on June 8.

From Shaila Dewan: “We proved that 11 weeks of a campaign can top 11 years of incumbency,” Mr. Halter said to a packed crowd that included union workers and Sierra Club environmentalists. “Today we put the political insiders and the special interest on the ropes, and in three weeks we’re gong to knock them out.”

Though Mr, Halter appears to have been the candidate to benefit the most from the millions of dollars poured into the race by outside groups, Ms. Lincoln far outraised him in traditional campaign fund-raising. “Today you proved that your votes and not their money are going to determine the future of Arkansas,” he said.

10:51 p.m.|Sestak Celebrates

“This is what democracy looks like,” Representative Joe Sestak says in his victory speech, touting his win over the establishment and over Washington D.C.

10:45 p.m.|Republican Take on Specter’s Loss

Michael Steele, the chairman of the Republican National Committee, didn’t hold back in interpreting Senator Specter’s loss in Pennsylvania as a dire warning for Democrats in November:

“Arlen Specter’s defeat tonight is yet another blow to President Obama and his vaunted political operation. Like fellow Democrats before him, Arlen Specter’s loss should strike fear in the hearts of Congressional Democrats who choose to embrace the President’s reckless liberal agenda despite the clear objections of their constituents because they thought the White House could bail them out.

“Now as he attempts to introduce himself to general election voters, Joe Sestak will have to bear the tremendous weight of having supported President Obama’s failed $862 billion stimulus and a massive government takeover of health care. Time after time, Joe Sestak has been a reliable vote for his Democrat bosses in Congress while his constituents at home are left without a voice.

10:39 p.m.|Mining Murtha’s Seat

From Carl Hulse: In a major bright spot for House Democrats, the party retained the seat of the late Representative John P. Murtha in southwestern Pennsylvania, continuing a streak of wins in contested special elections and showing Republicans that Democrats will not easily give up control of the House.

Though Democrats dominate in the district, its voters are blue-collar conservatives and it is exactly the type of swing district carried by John McCain in 2008 that Republicans must win if they are to reach their goal of taking control of the House in November. Tom Davis, a former Republican House member and top party campaign strategist, saw the win by Democrat Mark Critz, a former aide to Mr. Murtha, over Republican Tim Burns as a serious blow to the Republican claim to be within reach of the 40 seats needed to recapture the House.

“If you can’t win a seat that is trending Republican in a year like this, then where is the wave?” asked Mr. Davis, who said Republicans will need to examine what went wrong. “It would be a huge upset not to win this seat.”

Democrats saw the win as a huge morale booster.

10:34 p.m.|Critz Takes Murtha’s Seat

In the special election to replace longtime Representative John P. Murtha of Pennsylvania, Mark Critz, his longtime aide, appears to have won, according to early results. Mr. Critz defeated Tim Burns, a millionaire Republican.

Representative Chris Van Hollen, the chairman of the Democratic Congressional Campaign Committee, said: “This was the only race in the country today where a Democrat faced off against a Republican and the results are clear. Mark Critz focused on creating jobs for middle class families, while Republicans practiced the politics of fear and distortion.”

Stay tuned. A special election in Hawaii will be held this Saturday for the seat vacated by Representative Neil Abercrombie.

10:29 p.m.|Meanwhile in Arkansas

From Shaila Dewan — Everyone is waiting on returns. At pre-election-night-party cocktails on the back porch of Sheila Bronfman, longtime supporter of the Clintons and Little Rock Democratic activist, an assortment of political types reached a consensus: Senator Blanche Lincoln will squeak by, they predicted, without a runoff.

Hours earlier, Janine Parry, a political scientist at the University of Arkansas Fayetteville, made a similar, cautious prediction. She said that in the end, Arkansas farmers would not want to give up the Chairwoman of the Agriculture Committee, Ms. Lincoln’s powerful position, and that her recent proposal of a bill to curb derivative trading by Wall Street banks appealed to Arkansans. “If Arkansas is anti-anything, it’s anti-big institution,” she said.

At the home of Ms. Bronfman, a Lincoln supporter, the soothsaying was equally timid. No wagers were made.

Things were pretty mellow at the Bill Halter watch party (everyone in Arkansas calls them watch parties, not victory parties, in what is perhaps a telling disdain for euphemism). It was in the small Arkansas room of the Peabody Hotel, overlooking the river. Stale chips, guacamole with no kick, chicken tenders. A smattering of applause every time the television flashed the results, though at this early stage Mr. Halter and Senator Blanche Lincoln took turns taking the lead, while a third candidate, D.C. Morrison, had a whopping 14 percent of the vote with three counties reporting.

10:25 p.m.|Specter Concedes

From Katharine Q. Seelye: Mr. Specter just gave his concession speech.

“It has been a great privilege to serve the people of Pennsylvania,” he said, “and it’s been a great privilege to be in the United States Senate.”

He looked emotionally drained and wrapped his speech up quickly after thanking several supporters by name. “I’ll be working very, very hard for the people in the commonwealth in the coming months,” he said, before leaving the stage.

He thanked President Obama and Gov. Ed Rendell for their support.

10:19 p.m.|A.P. Calls for Sestak

The Associated Press has called the Democratic Senate race for Representative Joe Sestak over Senator Arlen Specter.

Senator Robert Menendez, the chairman of the Democratic Senatorial Campaign Committee, issued this statement, even though establishment Democrats hadn’t supported Mr. Sestak’s challenge to the incumbent, Senator Arlen Specter:

Tonight Pennsylvania Democrats nominated Joe Sestak, a former Naval Officer who has proven he takes a back seat to nobody when it comes to shaking-up Washington and taking on the establishment. Joe, an energetic campaigner, has a compelling personal profile and a message of change that resonates with voters, especially in this political environment.

Democrats enter the general election season with a number of advantages. Democrats enjoy a 14 percent party registration advantage, with 1.2 million more Democrats than Republicans. Four million new Democrats registered in 2008. President Obama carried Pennsylvania by double digits. Governor Rendell and Senator Casey remain well-liked.

With far less fanfare, Republicans today nominated a former Wall Street executive who made his money trading derivatives. While in Congress, he not only racked up an extreme right-wing voting record, but he also championed free-wheeling Wall Street practices. After five years in the House of Representatives, Toomey led the Wall Street backed Club for Growth, advocating for corporate interests like the big banks, oil companies, and insurance companies. While in Congress, Pat Toomey racked up a voting record that would make Rick Santorum look moderate. In fact, Toomey has a 97 percent lifetime conservative rating from the American Conservative Union – nine points higher than Santorum’s 88 percent.

For Democrats in Pennsylvania to be successful this November, we must be aggressive in framing the choice for voters. Democrat Joe Sestak is focused on creating jobs and the needs of the middle class, while Pat Toomey would do even more to protect the big banks, Wall Street, the oil companies and the insurance companies. Look no further than this week’s debate over Wall Street reform for the difference between the two candidates. Joe Sestak has already voted to hold the big banks accountable and Pat Toomey opposes common sense measures to reign-in the big banks. Given that we cannot return to the failed economic policies of the past, the stakes for November could not be higher.

Matt Rourke/Associated PressSpeaking in Gradyville, Pa., on Tuesday, Representative Joe Sestak was in a tight race in the Democratic Senate primary, threatening to end Senator Arlen Specter’s career.

10:16 p.m.|Specter Down

From Katharine Q. Seelye — Specter backers are very discouraged.

“It doesn’t look good for Arlen,” Mr. Rendell said. He blamed a low turnout in Philadelphia. While Mr. Specter is ahead in Philadelphia 2-1, he said, the numbers do not appear to be strong enough to offset Mr. Sestak’s lead elsewhere.

“The rain killed Arlen,” Mr. Rendell said. “Whatever chance he had went down with the rain.”

The two were running even in the suburbs, but Mr. Sestak was leading in Pittsburgh and elsewhere.

Ed Reinke/Associated PressRand Paul arrives in Bowling Green, Ky., to deliver his victory speech after winning the Republican nomination for Senate accompanied by family, including his wife, Carol, and father, Representative Ron Paul of Texas.

10:14 p.m.|Paul’s Message

From Kate Zernike — Rand Paul made clear in his remarks that the celebration at the Bowling Green Country Club was a Tea Party party. He declared himself a proud member of the movement, credited it for his victory, and dismissed speculation that he would have to abandon it to appeal to more moderate voters in the general election.

“I have a message, a message from the Tea Party, a message that is loud and clear and does not mince words,” he said. “We’ve come to take our government back. We’ve come to take our government back from the special interests who think that the federal government is their own personal ATM. From the politicians who bring us oversized fake checks emblazoned with their signature as if it was their money to give.”

“Washington is horribly broken,” he said. “I think we stand on a precipice, we are encountering a day of reckoning and this movement, this Tea Party movement is a message to Washington that we’re unhappy and that we want things done differently.”

“The tea party movement is huge. The mandate of our victory tonight is huge. What you have done and what we are doing can transform America.”

“The tea party movement is about saving the country from a mountain of debt that is devouring our country and I think could lead to chaos,” he said.

“People say to me, what can one man do? What can one Senator do? What I say to them is, it’s more than just me, its you, it’s a nationwide movement and what I say to Washington is, Watch out, here we come.”

“People are already saying now you need to weave and dodge, now you need to switch, now you need to give up your conservative message, you need to become a moderate, you need to give up the Tea Party, you need to distance yourself,” he said, to which the crowd yelled NO!

“The Tea Party message is not a radical message,” Mr. Paul said. “It’s not an extreme message. What is extreme is a $2 trillion deficit. That’s what’s extreme.”

The Tea Party message, he said, calls for things that are widely popular among Republicans, Democrats and Independents alike: term limits, a Constitutional Amendment to balance the budget, requiring new legislation to identify which portion of the Constitution authorizes it, and requiring members of Congress to read every bill before voting on it. “Who is opposed to them reading the bills?” he said. “Is that an extreme idea to read the bills? They tell me they want me to wait to buy a gun I tell them they need to wait to pass legislation.”

People who focus only on the signs and the rallies of the Tea Party, Mr. Paul suggested, miss its broad appeal and its impact.

“People say other incumbents will lose tonight, other establishment figrures may lose tonight, but it wasn’t the Tea Party that did it,” he said. “What is going on, though, is that there is a movement among the country, that people don’t like the arrogance, the arrogance of officialdom, the arrogance of power.”

But, he warned, change would require compromise.

“Tough choices will have to occur,” he said. “So many Republicans have been elected and they say ‘we’ll cut your taxes but then we’ll bring you home the pork.’ It’s coming to an end, because we can’t manage this debt.”

Update: Mr. Paul said Mr. McConnell had called him earlier in the evening to congratulate him and say that he would see him at the unity rally at Republican Party headquarters on Saturday.
CNN’s Jessica Yellin asked Mr. Paul if the Republican establishment should be worried tonight. He laughed and nodded. “I mean it in a friendly way, when I say Washington here we come,” he said. “I don’t mean it in a bellicose way.”

10:11 p.m.|Pa. Senate Race Is Tight So Far

From Katharine Q. Seelye in Philadelphia — Half the precincts in Pennsylvania have reported their results by now and the race could not be closer. It is 50-50 statewide.

In Philadelphia, where 70 percent of precincts have reported, Mr. Specter is ahead 62-38 percent. This is not as big of a lead as the Specter camp had hoped.

Results from the Philadelphia suburbs are too slim to be meaningful, but in Montgomery County, long a Specter base of support, Mr. Sestak is leading 55-45, but with just 17 percent of the vote in.

Mr. Sestak is also leading in Pittsburgh.

10:00 p.m.|Conway Is Up in Democratic Senate Primary

In Kentucky, there was indeed another primary for the Senate seat being vacated by Senator Jim Bunning. Attorney General Jack Conway has defeated Daniel Mongiardo to become the Democratic nominee, according to the latest call of The Associated Press. So that sets up Rand Paul versus Mr. Conway for the general election. — Kate Phillips

9:41 p.m.|A Father’s Legacy

From Kate Zernike in Bowling Green, Ky. — Ron Paul was mobbed by supporters before he could depart the stage where his son had thanked supporters – people asked him for autographs and told him that he was responsible for this victory, in the same way, one supporter said, that Barry Goldwater in the 1960s made Ronald Reagan’s victory in 1980 possible.

Reporters, too, wanted his take. What message does this send to Republicans? they asked.

“They ought to pay close attention to the grassroots,” Representative Paul said. “When Rand talks about the Tea Party movement it’s the same as saying talking to the grassroots people, and get rid of the power people, the people who run the show, the poeple who think they’re above everybody else, that’s what the people are sick and tired of, that’s the message.”

Should Republicans be worried? Representative Paul said that was not the word he would use.
“I would think that they might gain an incentive to move in our direction. Toward freedom, toward limited government, toward the Constitution.”

9:32 p.m.|For the Record

Just a note: Pat Toomey, the former Congressman and former head of Club for Growth, the anti-tax group, has of course won the Republican nomination for Senate in Pennsylvania. The Democratic primary is still rolling in close results, but Mr. Toomey will be a formidable opponent no matter which Democrat pulls out the win tonight.

9:13 p.m.|Girding for a Run-off in Arkansas

From Shaila Dewan in Arkansas — As the voting hours wended to a close, Lt. Gov. Bill Halter, refreshed after a 25-hour campaign spree the night before, made an appearance at a precinct in Hillcrest, a liberal enclave in Little Rock. He seemed to be sandbagging his expectations for the results. Mr. Halter said that even if he did not win outright, putting Senator Blanche Lincoln into a runoff would be a victory.

“I think any reasonable political observer would say that when a two-term incumbent senator and someone with 16 years of experience in Washington is put into a runoff in her own party primary, that’s a tough sign for the incumbent,” he said.

Then he reminded his audience that he had been running for only 11 weeks. “Most folks when they run statewide, it takes them 11 months,” he said. “Some folks work two, three years to get together a statewide campaign.”

Neemah Esmaeilpour for The New York TimesSenator Blanche Lincoln and her husband, left, encounter her primary opponent, Lt. Gov. Bill Halter, while campaigning at a polling station in Little Rock, Ark.

Just when Mr. Halter was saying that Ms. Lincoln’s proposal to regulate derivative trading on Wall Street had come ten years too late, the senator strolled by with her husband.

“And there she is!” he said. Ms. Lincoln replied, “Hey, Bill,” and, as if at a wedding reception, mentioned that she’d just met her opponent’s father-in-law.

9:09 p.m.|Tea Party Influence

8:56 p.m.|Late Night in Pa.?

From Katharine Q. Seelye in Philadelphia — The earliest returns from Pennsylvania show nothing. But they do indicate that it could be a long night here in the Keystone State.

“This will not be decided early,” an official said.

Polls closed at 8 o’clock. Officials had initially thought that the light turnout would make the counting go fairly quickly, but that does not appear to be the case.

At this point, Mr. Specter is leading in Philadelphia by about 2-1, officials said, but quickly cautioned not to read anything into that because so few precincts had reported their results.

Similarly, in the Lehigh Valley, a swing area and home to Mr. Toomey _ who will be the Republican to beat in the fall _ Mr. Sestak is slightly ahead.

Mr. Specter is ahead by a tiny amount in the northeast part of the state, which includes Scranton and Wilkes-Barre, but again, there is too little to go on at this point.

8:51 p.m.|Tea Party Call to Arms

In his victory speech, Rand Paul said: “I have a message. A message from the Tea Party. A message that is loud and clear and does not mince words. We have come to take our government back.”

David Kohl/Associated PressTrey Grayson gets a hug from his daughter Alex after delivering his concession speech for the Republican Senate nomination to Rand Paul. Mr. Grayson’s wife, Nancy, and younger daughter Kate joined him in Hebron, Ky.

“Audit the Fed!” one supporter yelled at Paul headquarters.

8:48 p.m.|The Pa. Candidates’ Digs

From Katharine Q. Seelye in Philadelphia — Mr. Sestak has set his primary night headquarters at the Valley Forge Military Academy and College in suburban Philadelphia. It may be best known to readers as the alma mater of the late J.D. Salinger, who attended in the 1930s and who used it as a model for Pencey Prep, the school that Holden Caulfield runs away from in “Catcher in the Rye.”

The academy is located in Mr. Sestak’s Congressional district, and it highlights his military background — he was an admiral in the Navy.

Mr. Specter, by contrast, is gathering at a hotel in downtown Philadelphia, a far more traditional venue. Mr. Specter lives in the city and it has long been his base of support.

The lion’s share of votes in statewide elections usually comes from Philadelphia, and that is especially the case in a Democratic primary.

8:43 p.m.|Paul’s Victory Speech

From Kate Zernike in Bowling Green, Ky. — Mr Paul arrived at the country club to the booming sounds of the Rush song he often quotes at rallies — the Canadian band, like Mr Paul and his father, is known for its libertarian view.

On the trail, he quoted a line from the song: “Glittering prizes and endless compromises shatter the illusion of integrity” saying equating the prizes and compromises to earmarks and backroom deals in Washington.

His father, Ron Paul, walked with him onto the stage.

8:39 p.m.|Tea Party Modesty

From Kate Zernike in Bowling Green, Ky. — David Adams, Mr Paul’s campaign manager — and the emcee of the first Kentucky Tea Party in Lexington in March 2009, said: “Today is a good day for the Tea Party, but it is not a great day. The greatest days lie ahead. We have a lot of work to do. Our budget is out of whack. The debt is large and growing, and we have a lot of work to do. The only thing we proved tonight is that we have the ability to do it.”

8:24 p.m.|Conservative Tough Talk

Richard Viguerie, the guru of Republican direct mail and now the chairman of ConservativeHQ.com issued a very strong statement following Mr. Paul’s victory in Kentucky:

If we had a parliamentary system of government, McConnell would be expected to resign.

“The elections results are a massive repudiation of McConnell and the Republican congressional leadership, which aggressively supported Grayson. Coming on the heels of Senator Robert Bennett’s defeat in Utah and the Republican Senatorial Committee’s previous support for Charlie Crist in Florida, it is clear that many Washington, D.C. GOP leaders are enormously out of touch with the base of the Republican Party, grassroots conservatives.

“The new conservatives who are being elected this year are different from the establishment types who went along with the big government policies of George W. Bush, Tom DeLay, Bill Frist, and others.

“The 2010 elections will be a tsunami of Biblical proportions. The voters are angry and frightened at the mess that politicians, as well as the leaders of most of America’s major institutions, have made of our country.

“Recent election defeats of establishment Republicans will cause congressional Republicans to become more outspoken in their opposition to President Obama’s nominees and legislative agenda. Few, if any, Republicans will risk being seen as working with Nancy Pelosi, Harry Reid, and other Democrats.”

— Kate Phillips

8:14 p.m.|Pa.’s Governor Plays Down Outcome for Democrats

From Katharine Q. Seelye in Philadelphia: Gov. Edward G. Rendell Jr., of Pennsylvania, who is one of Senator Arlen Specter’s strongest supporters, says that if Mr. Specter loses tonight, the loss should not be interpreted as part of a national trend.

Rather, he said, the race is a referendum on Mr. Specter, who switched to the Democratic Party last year after almost three decades as a Republican.

“None of these results should be taken as meaning anything,” the governor said in a chatty interview in his office here in Center City late this afternoon as he mulled the ins and outs of a race that has grabbed national attention. “If it’s about anything, it’s about the difficulties of party-switching.”

He noted that Mr. Specter and Representative Joe Sestak, who is putting up a ferocious challenge, have voted the same way on almost every bill that has come before them in the last year _ for the stimulus package, for health care.

“In fairness to Arlen,” Mr. Rendell added, “if the economy was ok and there was no anti-incumbent wave, this wouldn’t have been a close election. People do know that Arlen has done a lot for the state, even people who may not be voting for him.”

As the polls close, Mr. Rendell was not confident that his horse would win. If Mr. Specter pulls out a victory, he said, it would be in part because of the Democratic state party organization and the organizations in Philadelphia and Pittsburgh.

In southeast Pennsylvania, for example, he said, party workers reported during the day that voter turnout was exceptionally light. So they got Richard Trumka, the former head of the coal miners union and a native of that area, to make some automated calls to urge people to go to the polls. Later reports from the region said turnout was inching up.

“We’ve got cars to take people to the polls, occasional babysitters and we have something as silly as ponchos,” Mr. Rendell said. By that he means that when workers knock on doors and someone says they don’t want to go out and vote in the rain, that person is given a poncho.

“We say, ma’am, come on out and vote and we’ll give you this Specter poncho and you can keep it!” he said. There are about 6,000 Specter ponchos being handed out in Philadelphia.

But the low turnout has him down. “The turnout is terrible,” he said. He estimated that perhaps 25 percent of Democrats in Philadelphia would vote and perhaps 30 percent in the state, making that fairly low, even by primary standards.

“That doesn’t augur well for Arlen,” he said.

The most enthusiastic activists support Mr. Sestak, according to the polls. So a broader cross-section of voters could dilute those activist votes.

“The wider the base, the better Arlen does,” he said. “The activists have never forgiven him for voting with George Bush.”

Governor Rendell credits the Sestak campaign with a searing television commercial that showed former President Bush endorsing Mr. Specter.

“That was a devastating ad,” Mr. Rendell said, giving kudos to the Campaign Group, the Philadelphia political media firm headed by Neil Oxman. It was answered, eventually, by a commercial from the Specter campaign featuring President Obama heaping praise on Mr. Specter.

“If the Bush commercial was ‘serve,’ and it was a great serve, the Obama commercial was a good return,” he said.

The Sestak campaign defied the conventional wisdom that says Mr. Sestak should have defined himself early to voters because he was relatively unknown. Instead, Mr. Sestak focused chiefly on Mr. Specter and saying that he switched parties to save one job _ his own.

“It’s only recently that the Specter campaign, through surrogates like myself and Mayor Nutter, have fought back on the issue of Arlen being a Republican,” Mr. Rendell said. When Mr. Specter was a Republican, he said, helped both Republicans and Democrats. And his vote for the economic stimulus package actually created thousands of jobs, Mr. Rendell said.

“I would have made more of his courageous vote on the stimulus,” Mr. Rendell said.

At the same time, he thinks Mr. Sestak made a mistake by refusing to say that he would endorse Mr. Specter if Mr. Sestak lost. “That matters to rank and file Democrats,” Mr. Rendell said. “Because even if they don’t like either candidate, they want the party to hold on to the seat in November,” he said, when the Democratic nominee will face Representative Pat Toomey.

“If Sestak isn’t going to endorse Specter, then that shows he doesn’t care about holding the seat,” he said.

8:07 p.m.|Grayson Makes Concession Call

From Kate Zernike in Bowling Green, Ky. — Trey Grayson just called Mr. Paul’s campaign manager, David Adams, to congratulate him on a race well run. “He said he’ll say nice things about Rand tonight, and he’ll see us at the unity rally Saturday,” Mr. Adams said, saying he sounded “very sincere.”

8:02 p.m.|Polls Close in Pennsylvania

Jessica Kourkounis for The New York TimesSenator Arlen Specter shakes hands with a supporter after leaving a Philadelphia polling site.

One of the most-watched contests in the Keystone State is the Democratic primary between Senator Arlen Specter, who switched parties and is seeking a sixth term, and Representative Joe Sestak, who in recent weeks really moved into competitive territory.

7:52 p.m.|Democrats React to Paul Win

Tim Kaine, the chairman of the Democratic National Committee, sees a possible window for his party in the G.O.P. primary win for Rand Paul in Kentucky. Mr. Kaine released this statement, stinging Senator Mitch McConnell, the minority leader from the state who had endorsed Trey Grayson, Mr. Paul’s Republican opponent:

Today, Kentucky Republicans selected Rand Paul as their Senate nominee, handing Senate Minority Leader Mitch McConnell a stunning loss. In a show of weakness for the Minority Leader, and in a race that symbolized the fight over the heart and soul of the Republican Party, Rand Paul overcame McConnell’s handpicked candidate by a large margin. Unfortunately for Republicans, ordinary Americans are unlikely to be receptive to extreme candidates like Rand Paul in the general election this November.

“Rand Paul’s positions fail to resonate beyond the far-right Republican segment of the electorate that supported him tonight. Middle-class Kentucky voters want to elect a Senator with clear ideas about how to create jobs and opportunities for Kentucky families. But Rand Paul is more interested in talking about abolishing the Department of Education and disbanding the Federal Reserve than about supporting economic recovery.

“As a result, Democrats are now in a better position to win Kentucky’s open Senate seat. Disenfranchised Republicans and independent-minded voters – as well as long-time Democrats – will have a choice on the Democratic side of a candidate who reflects the values and priorities of Kentucky voters instead of one in Rand Paul whose ideas are outside of the political mainstream and which would do nothing to put Kentuckians to work, help them send their kids to college or make health care more affordable.”

— Kate Phillips

7:36 p.m.|A.P. Calls Kentucky Race for Paul

The Associated Press is calling the Republican Senate primary in Kentucky for Rand Paul, the Tea Party candidate who ran a full-throttled campaign against Trey Grayson, the secretary of state. CNN calls it that way, too.

From Bowling Green, Kate Zernike reports: “As the televisions announced that Dr. Paul won, the crowd of supporters gathered around the patio fireplace at his victory party at the Bowling Green Country Club erupted into cheers.”

7:35 p.m.|Back Stage in Kentucky — By Kate Zernike

The Paul campaign has painted Mr. Grayson as the very model of the country club Republican – referring to him in news releases by his full name, Charles Merwin Grayson III. And Mr. Grayson has been the more establishment candidate.

He was urged into the race by Senator Mitch McConnell, the Republican minority leader and the state’s senior senator. And his election strategy relied largely on traveling the state to meet with influential local leaders – judges, hospital executives, bank presidents. Dr. Paul, meanwhile, favored Tea Party events outside places like Ol Harvey’s Eats in Lawrenceburg. But for its victory party, the Paul campaign chose country club in Bowling Green, about two miles from Dr. Paul’s home. With its lush grounds and a roaring fire in every room, it is a far cry from most Tea Party rallies.

The race between Dr. Paul and Mr. Grayson has been something of a proxy fight between the state’s two sitting senators, Mr. McConnell and Jim Bunning, both Republicans. Mr. McConnell helped nudge Mr. Bunning out of running for re-election, but not before ensuring that Mr. Grayson, who has worked his way up through local politics since college, would run. That was apparently before anyone sensed the rise of Dr. Paul, which was fueled largely by Tea Party support and money flowing in through the online network from his father’s 2008 presidential bid.

Both senators withheld their official endorsements until the last weeks of the campaign – with Mr. Bunning coming out first, for Dr. Paul, and Mr. McConnell for Mr. Grayson. Today, several of Mr. Bunning’s staff members were here working for Dr. Paul. Mike Reynard, his communications director, who had been holding signs and calling voters in northern Kentucky, said that Mr. Bunning had encouraged his staff to take vacation to come work for Dr. Paul.

Mr. McConnell, however, has been saying nice things about Dr. Paul in the last couple of days. And regardless of who wins, he has invited Republicans to a “unity event” at state party headquarters this Saturday, which should reveal whether or not the two sides can work together after a bitter campaign.

7:06 p.m.|Kentucky Polls Are Closed

Results are beginning to trickle in for the Senate primary on the Republican side between Trey Grayson and Rand Paul.

6:49 p.m.|Primary Preview

Primary elections in three states today could offer some insights on the health of both political parties, a read on the Tea Party movement, the future of two well-known incumbent senators and what might happen this November.

Polls in Arkansas, Pennsylvania and Kentucky are beginning to close. (But for those of you asking, there are no exit polls, so be wary of people trying to make early predictions from turnout patterns.)

Before the real numbers start rolling in, here are a few things that we are going to be looking at:

1. In Kentucky, can Rand Paul, the eye surgeon and son of Representative Ron Paul, win the Republican Senate primary, and thus demonstrate just how much actual electoral power the Tea Party has?

Mr. Paul is running explicitly as a Tea Party candidate and against Trey Grayson, the Kentucky secretary of state. It is hard to find a better example of the grassroots versus the Republican establishment: Mr. Grayson has the support of Senator Mitch McConnell of Kentucky, the Senate minority leader. Two Democrats are fighting for the nomination there: Jack Conway, the attorney general, and Daniel Mongiardo, the lieutenant governor.

These things are often hard to game out, but Democrats and Republicans argue that Democrats would have a better chance should Mr. Paul win the nomination, because he would probably have a tougher time appealing to moderate voters.

Kate Zernike sent in this take from Bowling Green, Kentucky:

Polls are still open for another 15 minutes in western Kentucky, which is on Central time, but with results coming in from just two counties in the Eastern part of the state, Rand Paul’s campaign is feeling confident.

“It’s not going to be close,” said David Adams, Dr. Paul’s hyperkinetic campaign manager, who was the emcee of the first Kentucky Tea Party meeting last year. “It’s going to go fast.”

2. In Pennsylvania, Senator Arlen Specter, the Republican-turned Democrat, has found himself in a tough fight to win the Democratic nomination to return to the Senate against Representative Joe Sestak.

Mr. Specter has found it daunting to close the sale with Democratic primary voters, who tend to be the more committed partisans and who remember all those years when Mr. Specter was a Republican, albeit a moderate one. (The incumbent senator wasn’t helped by Mr. Sestak’s TV advertisement showing Mr. Specter and former President George W. Bush campaigning together.)

Mr. Specter ended this campaign presenting himself as a powerful figure in the Senate able to deliver for his state. By doing that, he is running against one of the dominant forces in this primary day, which is anti-incumbent fever.

3.) In Arkansas, Senator Blanche Lincoln, a Democrat, is facing a challenge on the left from Bill Halter, the lieutenant governor. Win or lose, Ms. Lincoln is one of the top targets for Republicans this fall. The winner there needs to get 50 percent to avoid a run-off, so one thing to watch for, should no one win, is how far below 50 percent does Ms. Lincoln place. That may indicate how big of a hurdle she may have, if she wins a run-off in June, by November.

4) Finally, people in Washington love to look at early Congressional elections as a test of what might happen in the November midterms, an exercise that often proves to be little more than a parlor room exercise. Still, in Pennsylvania, the special election race to succeed the late Representative John P. Murtha – between Mark Critz, a Democrat and long-time aide to Mr. Murtha, and Tim Burns, the Republican – could offer a test of just how strong the political organizations are for both parties, and how much Republican voters are engaged in Congressional races.

President Obama drew criticism on Thursday when he said, “we don’t have a strategy yet,” for military action against ISIS in Syria. Lawmakers will weigh in on Mr. Obama’s comments on the Sunday shows.Read more…